This is information, not a recommendation. We do not advise you to take anything. Under 18 or with an eating disorder, including a past one: this text is not aimed at you, and you will find places to turn to under When to get medical advice. During pregnancy or breastfeeding, with kidney disease or on medication, ask a doctor first.
What omega-3 is
This usually means three fatty acids: ALA from plants, and EPA and DHA from oily fish and algae. According to EFSA, recommendations for adults in Europe lie at 250 to 500 mg of EPA and DHA a day.[3]
What may be said in the EU
| Authorised claim | Condition |
|---|---|
| “EPA and DHA contribute to the normal function of the heart” | Beneficial effect with 250 mg of EPA and DHA a day, only for foods that are at least a source of omega-3 fatty acids[2] |
| “DHA contributes to maintenance of normal brain function” | At least 40 mg of DHA per 100 g and per 100 kcal, beneficial effect with 250 mg of DHA a day[2] |
| “DHA contributes to the maintenance of normal vision” | At least 40 mg of DHA per 100 g and per 100 kcal, beneficial effect with 250 mg of DHA a day[2] |
| “DHA and EPA contribute to the maintenance of normal blood triglyceride levels” | Daily intake of 2 g of EPA and DHA, plus the note not to exceed 5 g a day in total[2] |
| “DHA and EPA contribute to the maintenance of normal blood pressure” | Daily intake of 3 g of EPA and DHA, plus the note not to exceed 5 g a day in total[2] |
No claim is authorised on losing weight or building muscle.[4]
What studies show
| Topic | What was studied | Result |
|---|---|---|
| Heart and circulation | Cochrane review of 86 trials with 162,796 people | Little or no effect on overall deaths and cardiovascular events, a small difference in coronary events with low certainty[1] |
| Weight | 21 trials in overweight and obesity | No effect on weight or BMI. Waist and waist-to-hip ratio showed differences, but the researchers do not see a role in weight loss as shown[5] |
| Strength and lean mass | 2026 analysis in healthy adults | No clear evidence, and the certainty of the data is very low[6] |
| Older adults | 1,054 people over 2 years at 1 g a day | No differences in handgrip or walking speed[7] |
| Muscle soreness | 43 studies, 9 of them pooled | Less soreness after unaccustomed exercise in those 9 studies, but the overall picture is mixed and the studies have clear weaknesses[8] |
Limits and risks
EFSA sees no safety concerns for adults up to 5 g of EPA and DHA combined a day, and up to 1.8 g of EPA alone.[3] For DHA alone, it confirmed the safe level of 1 g a day in 2026.[9] There is no formal upper limit.[3][9] With 2 to 6 g of EPA and DHA a day, LDL cholesterol rose by about 3% in studies, which according to EFSA may not worsen cardiovascular risk.[3]
Still, “more is better” is wrong here. In 7 large trials with 81,210 people, 65 years old on average, atrial fibrillation occurred more often with omega-3. The risk was higher above 1 g a day than at up to 1 g.[10]
On bleeding, an analysis of 11 trials with 120,643 people found no overall difference, but a slightly higher risk with high-dose purified EPA.[11]
- Blood thinners: At high doses, fish oil can affect platelets and might prolong clotting times with warfarin, although most studies found no clear effect at 3 to 6 g a day.[12] Ask a doctor first.
- Heart rhythm problems and surgery: Ask a doctor first.
- Possible complaints: unpleasant taste, bad breath, heartburn, nausea, stomach and gut discomfort and diarrhoea.[12]
- Pregnancy and breastfeeding: DHA has its own claims and amounts. Clarify them with a doctor.[4]
The app does not replace medical advice.
Related
Sources
- Abdelhamid AS et al.: Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database Syst Rev, 2020
- Regulation (EU) No 432/2012 establishing a list of permitted health claims, consolidated version
- EFSA: Scientific Opinion on the Tolerable Upper Intake Level of EPA, DHA and DPA, 2012
- European Commission: EU Register on nutrition and health claims, accessed November 2026
- Du S et al.: Does Fish Oil Have an Anti-Obesity Effect in Overweight/Obese Adults? A Meta-Analysis of Randomized Controlled Trials. PLoS One, 2015
- Silva AMF et al.: Omega-3 supplementation shows no clear benefit for fat-free mass or muscle strength in healthy adults: a systematic review and meta-analysis of randomized controlled trials. Nutrition, 2026
- Chou SH et al.: Effects of Supplemental Vitamin D3, Omega-3 Fatty Acids on Physical Performance Measures in the VITamin D and OmegA-3 TriaL. J Clin Endocrinol Metab, 2024
- Yaghoobi E et al.: Effects of LC n-3 PUFA Supplementation on Muscle Pain, Function, and Damage Markers in Healthy Young to Middle-Aged Adults Following Acute or Chronic Exercise: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients, 2026
- EFSA: Scientific Opinion on the tolerable upper intake level for supplemental docosahexaenoic acid, 2026
- Gencer B et al.: Effect of Long-Term Marine ɷ-3 Fatty Acids Supplementation on the Risk of Atrial Fibrillation in Randomized Controlled Trials of Cardiovascular Outcomes: A Systematic Review and Meta-Analysis. Circulation, 2021
- Javaid M et al.: Bleeding Risk in Patients Receiving Omega-3 Polyunsaturated Fatty Acids: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. J Am Heart Assoc, 2024
- NIH Office of Dietary Supplements: Omega-3 Fatty Acids, Fact Sheet for Health Professionals